Conventionally, there is known the Digital Audio Tape (DAT) as a system for recording and reproducing digital data, in particular digital data of music, to and from a magnetic tape. Also, there is used the Digital Data Storage (DDS) as a system for recording and reproducing digital data of large capacity (several G bytes˜scores of G Bytes) stored in a computer to and from a magnetic tape based on the DAT.
In the DDS, inclined tracks are recorded to a magnetic tape using a tape streamer of the helical scanning type having rotary heads. In each of the tracks, there are recorded 96 data blocks called fragments. In each of the fragments, a fragment ID to discriminate the respective fragments from others is recorded other than recording data.
In a recording and/or reproducing apparatus of the DDS, read after write (RAW) processing is performed to monitor whether or not fragments are normally recorded. In case a fragment is not normally recorded, rewrite processing is performed to rewrite a track including the fragment entirely to another position.
In the rewrite processing, even though there is raised only one fragment which is not normally recorded, a track including the fragment is rewritten entirely to another track. Also, since several tracks during a period from the time when a fragment which is not normally recorded is detected and until the time when the rewrite processing is performed are caused to be dummy, there is raised a problem that loss of tape capacity is enlarged.